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通过对历史文献资料的收集、统计和分析,对1644-1911年西海固地区干旱灾害的时间变化、空间变化、等级序列以及驱动力因子进行了研究。结果表明:1644-1911年西海固地区有记载的干旱灾害82次,平均3.27年发生一次;旱灾以春旱和夏旱最多,占发生次数的38.5%和25.3%;西海固地区的干旱灾害划分出四个等级序列,共发生轻度旱灾24次,占旱灾总数的29.3%;发生中度旱灾50次,占旱灾总数的60.97%;发生大旱灾和特大旱灾共8次,占旱灾总数的9.73%;西海固发生干旱灾害可分为5个阶段:旱灾的多发期包括:1710-1770年代、1800-1860年代(1820年代除外)。少旱灾期包括:1640年代-1700年代、1780-1790年代、1870-1910年代(1890年代除外);这一时期的中期西海固发生干旱灾害发生频率较高;旱灾高发区主要集中在西海固与陕西交接的南部,其中固原发生干旱的频次远远高于其他地区;影响干旱灾害时空变化的驱动力因子包括气候、生态和人口因子,其中气候因子起到了决定的作用。
Through the collection, statistics and analysis of historical documents, the temporal changes, spatial changes, rank sequences and driving forces of drought disaster in Xihaogu area from 1644 to 1911 were studied. The results showed that there were 82 drought disasters recorded in Xihaigu area from 1644 to 1911, with an average of 3.27 years. The drought was highest in spring drought and summer drought, accounting for 38.5% and 25.3% of the occurring frequency. The division of drought disaster in Xihaigu area A total of four grades were recorded, with 24 minor drought and 29.3% of the total number of drought; moderate drought 50 times, accounting for 60.97% of the total number of drought; 8 major and major drought, accounting for 9.73 %; The drought disaster in Xihaigu can be divided into five stages: the multiple periods of drought include: 1710-1770s, 1800-1860s (except 1820s). The less drought periods include: the 1640s - 1700s, 1780s - 1790s, 1870s - 1910s (except the 1890s); during this period, the occurrence frequency of drought in Xihaigu was higher in this period; the high incidence of drought was mainly concentrated in Xihaigu The frequency of drought in Guyuan is much higher than that in other areas in the southern part of Shaanxi. The driving forces that affect the temporal and spatial changes of drought disasters include climate, ecology and population factors, and the climate factor plays a decisive role.